Develop and test with Node.js 26

.devcontainer/devcontainer.json

@@ -14,7 +14,7 @@
       "version": "latest"
     },
     "ghcr.io/devcontainers/features/node:1": {
-      "version": "22",
+      "version": "26",
       "installYarnUsingApt": false
     }
   },

.devcontainer/postCreate.sh

@@ -3,5 +3,6 @@
 # Install dev dependencies from OPAM
 opam install . --with-test --with-dev-setup -y
 
-corepack enable
+# The Node feature provides yarn: it enables corepack where Node still bundles
+# it (Node 24 and older) and installs yarn with npm otherwise.
 printf "\n" | yarn 

.github/workflows/changelog.yml

@@ -28,7 +28,7 @@ jobs:
       - uses: actions/setup-node@v7
         with:
           cache: yarn
-          node-version: 22
+          node-version-file: .nvmrc
       # The scripts import semver. Package builds aren't needed for them.
       - run: yarn install --immutable --mode=skip-build
       - run: node --test scripts/changelog.test.js scripts/magicNumbers.test.js

.github/workflows/ci.yml

@@ -587,14 +587,19 @@ jobs:
           fi
           echo "path=$dir" >> "$GITHUB_OUTPUT"
           cp -r tests/package_tests/installation_test/* "$dir"
+          # The compiled stdlib tests run against the installed runtime. Their
+          # Test.mjs imports @babel/code-frame, which tests/tests depends on.
+          cp -r tests/tests/src/stdlib "$dir/stdlib"
+          echo "code-frame=$(node -p 'require("./tests/tests/package.json").dependencies["@babel/code-frame"]')" >> "$GITHUB_OUTPUT"
 
       - name: Install ReScript package
         run: |
           COMMIT_SHA="${{ needs.pkg-pr-new.outputs.commit_sha }}"
           npm i --no-audit \
             "https://pkg.pr.new/rescript-lang/rescript@${COMMIT_SHA}" \
             "https://pkg.pr.new/rescript-lang/rescript/@rescript/runtime@${COMMIT_SHA}" \
-            "https://pkg.pr.new/rescript-lang/rescript/@rescript/belt@${COMMIT_SHA}"
+            "https://pkg.pr.new/rescript-lang/rescript/@rescript/belt@${COMMIT_SHA}" \
+            "@babel/code-frame@${{ steps.tmp-dir.outputs.code-frame }}"
         shell: bash
         working-directory: ${{ steps.tmp-dir.outputs.path }}
 
@@ -618,6 +623,16 @@ jobs:
         shell: bash
         working-directory: ${{ steps.tmp-dir.outputs.path }}
 
+      # build-compiler runs the stdlib tests on the Node.js version in .nvmrc,
+      # this job on the oldest supported one, so tests of APIs missing there
+      # must stay out of Stdlib_TestSuite and Stdlib_TempTests.
+      - name: Run stdlib tests
+        run: |
+          node stdlib/Stdlib_TestSuite.mjs
+          node stdlib/Stdlib_TempTests.mjs
+        shell: bash
+        working-directory: ${{ steps.tmp-dir.outputs.path }}
+
   test-installation-pnpm:
     needs:
       - pkg-pr-new
@@ -657,6 +672,10 @@ jobs:
           fi
           echo "path=$dir" >> "$GITHUB_OUTPUT"
           cp -r tests/package_tests/installation_test/* "$dir"
+          # The compiled stdlib tests run against the installed runtime. Their
+          # Test.mjs imports @babel/code-frame, which tests/tests depends on.
+          cp -r tests/tests/src/stdlib "$dir/stdlib"
+          echo "code-frame=$(node -p 'require("./tests/tests/package.json").dependencies["@babel/code-frame"]')" >> "$GITHUB_OUTPUT"
 
       - name: Install ReScript package
         run: |
@@ -665,7 +684,8 @@ jobs:
           pnpm --config.block-exotic-subdeps=false i \
             "https://pkg.pr.new/rescript-lang/rescript@${COMMIT_SHA}" \
             "https://pkg.pr.new/rescript-lang/rescript/@rescript/runtime@${COMMIT_SHA}" \
-            "https://pkg.pr.new/rescript-lang/rescript/@rescript/belt@${COMMIT_SHA}"
+            "https://pkg.pr.new/rescript-lang/rescript/@rescript/belt@${COMMIT_SHA}" \
+            "@babel/code-frame@${{ steps.tmp-dir.outputs.code-frame }}"
         shell: bash
         working-directory: ${{ steps.tmp-dir.outputs.path }}
 
@@ -684,6 +704,16 @@ jobs:
         shell: bash
         working-directory: ${{ steps.tmp-dir.outputs.path }}
 
+      # build-compiler runs the stdlib tests on the Node.js version in .nvmrc,
+      # this job on the oldest supported one, so tests of APIs missing there
+      # must stay out of Stdlib_TestSuite and Stdlib_TempTests.
+      - name: Run stdlib tests
+        run: |
+          node stdlib/Stdlib_TestSuite.mjs
+          node stdlib/Stdlib_TempTests.mjs
+        shell: bash
+        working-directory: ${{ steps.tmp-dir.outputs.path }}
+
   # The single CI check that the master ruleset requires. Matrix job names
   # contain runner labels, so requiring this job instead keeps the ruleset
   # unchanged when runners or jobs change. It runs even when a needed job fails

.nvmrc

@@ -1 +1 @@
-22
+26

CONTRIBUTING.md

@@ -32,7 +32,7 @@ algorithm and representation invariants belong beside their implementation.
 
 > Most of our contributors are working on Apple machines, so all our instructions are currently macOS / Linux centric. Contributions for Windows development welcome!
 
-- [Node.js](https://nodejs.org/) v22.x or newer
+- [Node.js](https://nodejs.org/) v26.x or newer (the version in `.nvmrc`)
 - [Yarn CLI](https://yarnpkg.com/getting-started/install) (can be installed with `corepack`, Homebrew, etc)
 - C compiler toolchain (usually installed with `xcode` on Mac)
 - Rust toolchain (required to build rewatch; follow the instructions at https://www.rust-lang.org/tools/install and install the version listed as `rust-version` in `rewatch/Cargo.toml`)

changes/node-26-dev.internal.md

@@ -0,0 +1 @@
+- Develop and test with Node.js 26, and run the stdlib tests in the installation tests on Node.js 22, the oldest supported version.

tests/tests/src/stdlib/Stdlib_TestSuite.res

@@ -1,3 +1,7 @@
+// The installation tests in .github/workflows/ci.yml also run this suite on
+// the oldest supported Node.js version, 22. Tests of APIs that Node.js 22
+// lacks belong in a separate entry point that only scripts/test.js runs.
+
 include Stdlib_TestTests
 include Stdlib_PromiseTest
 include Stdlib_ErrorTests